On Friday, Mike Chappell responded to questions from Colts fans in his “ask the expert” series. In his piece, he mentioned that the team recently brought in veteran cornerbacks Frank Walker and Deshea Townsend for visits.

In Chappell’s opinion, the Colts are actively pursuing potential veteran support at cornerback. This would be a logical move for the team, given that third round pick Kevin Thomas suffered a knee injury during rookie camp and will likely miss the rest of the season.

The obvious question that need to be answered is — if the Colts actually do plan on signing a veteran corner, who will it be?

Frank Walker is 5-foot 11-inches tall, weighs 200 pounds, and is entering his seventh season as a cornerback in the NFL. Last year, he played for the Baltimore Ravens as a backup and started in only one game. Walker had his best season in 2008, playing in 15 games — starting five — and produced 31 tackles, 1 interception, and 11 passes defended.

Townsend is 5-foot 10-inches tall, weighs 190 pounds, and is entering his twelfth season as a cornerback in the NFL. He has spent his entire career in Pittsburgh and formerly started from the 2004 to 2007 seasons. Townsend is now 34 years old and spent his last two seasons as a backup — starting five — and produced 47 tackles, 3 interceptions, and 11 passes defended in that span.

These players suggest two things. First, the Colts are not afraid to look at players who are reaching the twilight of their careers. Second, they do not seem to be focused on finding starting caliber talent, but only an experienced backup for insurance should the rookies or Terrail Lambert fail to workout in training camp.

The first player that comes to mind for me, as one the Colts should target, is Keiwan Ratliff. Ratliff is 5-foot 11-inches tall, weighs 188 pounds, and was cut by the Cincinnati Bengals on June 18th. He has experience in the Colts system and was a serviceable backup in 2008, when he totaled 32 tackles, 2 interceptions (he returned one for a touchdown), and 5 passes defended. Frankly, I was surprised that Ratliff was so quickly dismissed in 2009 and think he would bring enough experience and value to the roster that he would be worth a close look.

The second player that sticks out is a potential return for Nick Harper. Harper played six years with the Colts and is entering his ninth NFL season. At 5-foot 10-inches tall and 182 pounds, Harper fits the mold of the kind of cornerback the Colts covet. The problem with Harper is that he really fits the old Colts mold for corners, in that he excels in zone and against the run but is weak in man coverage. He also has struggled to stay healthy in Tennesse and the toll on his body may make it undesirable for the Colts to go in his direction.

Four other corners could be on the Colts radar. Ken Lucas, Samari Rolle, Fred Smoot, and Will Allen are all in their early thirties, but that is still younger than Townsend. They all have a lot of NFL experience and could be stop-gap solutions should the Colts feel they need someone proven in the NFL behind Hayden, Powers, and Lacey.

It will be interesting to see if the team chooses to sign a free agent during training camp and the preseason, or wait until the regular season arrives — if at all. It seems every year the Colts sign one or two free agents, or players off of waivers, prior to the start of the new season. If they sign a cornerback, who will it be?